Allen (defendant) was a defendant in a criminal trial. Despite repeated warnings from the judge, Allen was highly disruptive and antagonistic. The judge ordered Allen’s removal so that the trial could be conducted outside his presence, but later allowed Allen to return. When Allen resumed the unruly behavior, the judge again ordered removal. Allen was permitted to return for the rest of the trial upon his promise to behave. After conviction, Allen appealed. The court of appeals held that a criminal defendant can never be denied the right to be present for trial. The United States Supreme Court granted certiorari to consider whether the Sixth Amendment prohibits removal of an unruly and highly disruptive criminal defendant.